【作者】 潘良金；

【导师】 朱旭容；

【作者基本信息】 南京工业大学 ， 化学工程， 2003， 硕士

【摘要】 本文对对三氟甲基苯胺的合成进行了研究，即先由对硝基甲苯与溴素进行第一步溴化反应制得对硝基二溴苄，然后与次溴酸钠溶液进行第二步溴化反应制得对硝基三溴苄，再经过氟化、还原制得对三氟甲基苯胺。在第一步溴化反应中，考察反应温度、滴溴速度对反应的影响，发现第一步溴化反应的主要影响因素是温度。通过改进反应装置，使温度变化在2℃范围内，得到了较好的效果。在第二步溴化反应中，通过使用相转移催化剂(PTC)，使对硝基三溴苄的收率达到90％(mol)，对硝基三溴苄含量为94％。用HF为氟化剂进行氟化取代得对硝基三氟苄，含量为98％，经镍催化剂氢化还原，得到含量为97％的对三氟甲基苯胺。将氢化还原所得的粗对三氟甲基苯胺精馏(23块理论板，回流比12，压力15.8Kpa)，取83℃馏分，对三氟甲基苯胺收率为96％，色谱测得含量为99.3％。对三氟甲基苯胺的总收率的收率为84.3％。本文采用了熔点测定、气相色谱、薄层色谱等分析方法，并利用薄层色谱跟踪反应和决定反应终点，根据分析结果对反应的条件进行改进。本文还对反应中溴素的回收、溴盐的处理进行了研究。更多还原

【Abstract】 The paper reviews the exploration and the improvement for the preparation of p-nitrotoluene to p-aminobenzotrifluoride . The first step is the conversion of p-nitrotoluene to p-nitrobenzyl bromide. Then it reacts with HF and H2, 99.1% yield of p-aminobenzotrifluoride obtained. The second step is the conversion of p-nitrobenzyl bromide to p-nitrobenzaltribromide by reaction with sodium hypobromite. In the process of the first step it is found that reaction temperature is the most important factor to increase the yield. The yield of p-nitrobenzaltribromide is higher than unimproved one when, with the improvement of equipment, the change of temperature can be controlled in 2 . The second step is a two-phase water-organic solvent system .To give higher yield in a shorter reaction time, phase transfer catalyst (PTC) is applied for 90% (mol) yield. Then p-nitrobenzaltribromide reacts with HF,98% purity of p-nitrobenzotrifuoride obtained. With the catalyst of Ni applied, 97%purity of p-aminobenzotri-Fluoride is obtained. The amine is distilled under reduced pressure. Boiling at 83 (15.8KPa),the purity of p-aminobenzotrifluoride is 99.3%. The yield is 84.3%.The control of process and results of the preparation are illustrated by thin layer chromatography (TLC). The reutilization of bromine , the dispose of bromide are discussed.更多还原